Incorrect billing and poor customer care

I took a contract with Telkom on the 20th of May and i was informed i would be charged pro-rata for May in June. When June came i had a bill where the entire month of May was charged in full with only the data being pro-rata. When i tried to contact customer care, the phone kept ringing ( for over an hour ) and eventually cut due to poor reception. Its disappointing how taking a contract takes 10 minutes and customer care never works, especially considering i had to take the device back for out the box failure.